Propeixer



$- T. CARTER Sept. 13, 1932.

PROPELLER Filed March 15, 1929 3 Sheets-Sheet l Sept. 13, 1932. 5 CARTER 1,876,608

PROPELLER Filed March 15, 1929 5 Sheets-Sheet 2 INVENTOR P 1932- s. T. CARTER 1,876,608

PROPELLER Filed llarch 15, 1929 3 Sheets-Sheet 3 Patented Sept. 13, 1932 PATENT OFFICE SIDNEY '1. CARTER, OI PARNASSUS, PENNSYLVANIA PBOPELLER Application filed March 15, 1829. Serial No. 347,431.

This invention relates to propellers and more particularly to air propellers such as are employed on airplanes and the like.

An object of this invention is to provide a device of the type set forth constructed and rangement as to enable the direction of the thrust to be changed at will.

A still further object is to provide a device of the type set forth of rugged construction which will be effective and reliable in operation and relatively cheap to manufac-' ture and assemble.

These and other objects which will be apparent to those skilled in this particular art are accomplished by means of the invention illustrated in the accompanying drawings in which Fig. 1 is a view in side elevation of a propeller mechanism constructed in accordance with one embodiment of this invention, certain of the parts being broken away. Fig. 2 is a transverse sectional view through the mechanism illustrated in Fig. 1. Fig. 3 is a sectional view of certain details of construction through the brake drum mechanism. Fig. 4 is a transverse sectional View on the line III-III of Fig. 2, and Fig. 5 is a partial prspective view of certain of the elements shown in Fig. 4.

The particular embodiment of the present invention which has ben chosen for the purposes of illustration is adapted for operation with the usual t pe of propeller mechanism and consists 0 means for rotating the propeller blades in their sockets upon their axes for the purpose of varying the pitch of the blades or for the purpose of actually reversing such pitch when desired. Suitable means are connected directly to the propeller blades and revolve therewith for the purpose of shifting the blades about their axes or for definitely holding them against such movement in adjusted position. Means is provided for operating the shifting mechanism so as to cause a relatively small degree of rotation for the purpose of varying the pitch of the blades and additional means is provided for the purpose of so operating the shifting mechanism as to cause an actual reversal in the pitch of the blades.

The present invention is shown in connection with a porpeller having two blades and 11 secured on stubs 12 projecting outwardly from a hub 13 rigidly secured to a propeller shaft 14. Each propeller blade is rotatably supported upon its associated stub 12 and shifting mechanism is connected to each propeller blade for rotating the same about its axis to either variably ad'ust or reverse the pitch. It will be readily understood by those skilled in this particular art that, although the drawings and description herein refer to mechanism directly connected to one blade only, the shifting mechanism is connected to the opposite blade on the opposite side of the crank shaft.

As illustrated, the blade shifting mechanism includes a bracket 15, see Fig. 1, which is rigidly secured to the blade and which is connected by a connecting link 16 to a crank 17 of a blade shifting crank shaft 18 rotatably mounted in a shaft supporting bracket 19 which is part of a sleeve 20 feathered to an annular projection 21 of the hub 13 so as to be rotatable therewith and permit the sleeve 20 and shaft supportin bracket 19 to be moved longitudinally of t e casting toward and from the propeller blades. It will, of course, be understood that the blade 10 is connected in the same way to a similar duplicate crank shaft on the other side of the propeller shaft from that illustrated in Fig. 1.

A gear 22 is secured to the shaft 18 on the opposite side of the bracket 19 from the crank 17 and meshes with reversing gear teeth 23 formed on a wheel 24 having four diametrically opposed lugs 25, see Figs. 2, 3 and 4, on the face opposite the face provided with the gear teeth 23. The wheel is rotatably supported on the sleeve 20 adjacent a pair of oppositely disposed, radially proecting lugs 26 formed thereon. A pawl 27 having an elongated slot 28 loosely engaging a pin 29 extending outwardly from the end of the arm 26 engages the two opposite teeth 30 of the four formed on the outer surface of the wheel 24, see Figs. 4 and 5, for the purpose of normally holding the wheel 24 and gear 23 against rotation in one direction with relation to the hub 13,propeller shaft 14 and propeller blades 10 and 11. A spring holding pin 31 and coil spring 32 connected to a pawl arm 33 normally press the pawl inwardly toward the wheel.

A sleeve member 34 is keyed to the sleeve 20 and is provided with four ratchet teeth 35, see Figs. 2, 3 and 4, the two opposite teeth of which are normally engaged by pawls 36 mounted on the adjacent face of the wheel 24 and pressed into engagement with the teeth by suitable springs 37 for holding the wheel against rotation in the other direction.

A brake drum 38, see Figs. 1, 2 and 5 and which is indicated in dotted lines in Fig. 4, is rotatably mounted on the sleeve member 34 and is provided with a more or less extended cylindrical surface for cooperating with an associated brake shoe 39 pivotally mounted in the end of a brake lever 40 pivoted in a brake lever supporting bracket 41 and having the opposite end thereof associated with a pressure chamber 42 connected by a pressure line 43 with a pressure chamber 44 actuated by a piston 45 through a lever 46 or the like. The brake lever supporting bracket 41 is mounted on a stationary frame 47 while the brake drum 38 normally rotates with the hereinbefore described mechanism supported upon and secured to the propeller shaft. The edge of the brake drum adjacent the associated wheel 24 is provided with four radially extending beveled lugs 48 which are adapted to cooperate with pins 49 mounted on the wheel holding pawls 27, see Figs. 4 and 5, for the purpose of freeing the pawls 27 from such lugs to permit rotation of the wheel and associated gear teeth 23 at the desired time. The brake drum is positioned on the sleeve member 34 between the end of said member and the inner race 50 of a ball bearing having the outer race 51 mounted in a bracket 52 threaded to the hub 53 of a gear 54 rotatably mounted on the stationary frame 47 and connected through a beveled pinion 55 and flexible drive 56 with a crank wheel 57. The outer race 51 and connected parts are normally stationary, the ball bearing being provided to eliminate friction between such parts and the associated rotating parts mounted on the propeller shaft.

The face of the brake drum adjacent the wheel 24 is provided with diametrically opposed elongated lugs 58, as indicated in Fig. 4, which coo erate with the lugs 25 on the wheel 24 as ereinafter described. Springs 59 are located between the adjacent faces of the brake drum and the wheel member 24 and are so connected, one end to one member and the other end to the other member, as to normally hold the brake drum in the position indicated in dotted lines in Fig. 4 with relation to the wheel 24, but it will be apparent that the brake drum is rotatable with relation to such wheel.

It will be apparent that the rotation of the shaft 14 and associated propeller blades carries with it the blade shifting mechanism supported on the sleeve 20 which is keyed as at K to the extension 21 of the propeller blade supporting hub 13. The wheel 24 is geared directly tothe propeller shifting gears 22 and is held against movement by 7 being locked against movement in one direction by the pawls 27 secured to the bracket extensions 26, and against movement in the opposite direction by engagement of the wheel supported pawls 36 with the associated ratchet teeth 35 formed in the sleeve member 34 keyed to the sleeve 20 as at K.

The brake drum 38 and its lugs 58 being yieldingly held in the position indicated in dotted lines in Fig. 4 with relation to the associated lugs 25 of the wheel 24, by means of the helical springs 59, and assuming the parts to be rotating with the propeller blades, it will be apparent that the application of the brake shoe 39 to the brake drum through the medium of the operating lever 46, will put a drag upon the further rotation of the brake drum so as to cause the same to lag behind the associated parts including the wheel 24, or, in other words, to cause relative rotation between the brake drum and the wheel so as to cause the beveled lugs 48, see Fig. 5, to move upwardly under the pin 49 on the pawl, 27 so as to lift the pawl. away from the tooth 30 and free the wheel 24 therefrom. It will be understood that the two diametrically opposed lugs 48 operate simultaneously upon the two opposite pawls 27 shown in Fig. 4

When the pawls 27 are lifted away from the associated teeth 30, the spring 32 causes the pawl to move to the right as seen in Fig. 5, such movement being permitted by the elongated slot 28 connecting the pawl to the supporting pin 29. This results in the tooth engaging point of the pawl being moved past the tooth and resting on the periphery of the Wheel 24. The latter is now free to rotate in one direction with relation to the associated apparatus for a quarter of a turn or until the next succeeding tooth 30 is brought around to engage with the pawl 27. This rotation results from the engagement of the lugs 58 moving into contact with the lugs 25 on the wheel 24 and the latter is rotated a quarter of a turn until the next succeeding teeth 30 are engaged by the holding pawls 27. It will be apparent that this movement of the wheel has also moved the pawls 36 secured thereto a quarter of a revolution into engagement with the next succeeding teeth 35 on the sleeve member 34. The pawls 27 definitely prevent the further rotation of the wheel 24 and this in turn prevents the further rotation of the brake drum 38 so that as the brake shoe 39 is still held in contact therewith, it will merely result in slipping of the brake drum against the resistance of such brake shoe until the latter is released. Upon the release of the foot pedal 46, the brake shoe is released whereby the abovedescribed elements return to the position indicated by the fulland broken lines of Fig. 4.

It will be understood that in this description the expression rotation in reality refers to relative rotation of the parts mentioned, as all parts are rotating rapidly with the propeller shaft during the entire operation.

It will also be apparent that the rotation of the wheel 24 and the gear 23 through a quarter of a revolution has rotated the propeller reversing gears 22, meshing therewith, through a half revolution, the gears 22 being one half the size of the gear 23. This half revolution has moved the crank 17 through an arc of 180 until it points in the direction opposite to that illustrated in Fig. 1. This in turn has shifted the propeller blades 10 and 11 about their axes to an extent suflicient to reverse the pitch thereof and they are held in this reversed position until the entire operation is again repeated when they are returned to the positions indicated in Fig. 1. T

Merely varying the pitch of the blades, as distinguished from actual reversal thereof, is accomplished by rotation of the hand wheel 57 which in turn, through the flexible drive 56, rotates the pitch adjusting gear 54 and hub 53 threaded to the bracket 52 as at T. This results in an inward or outward movement of the bracket 52 which in turn moves the entire mechanism, including the sleeve member 20, longitudinally along the projection 21 of the propeller supporting hub. Obviously, this moves the crank shaft 18 toward or from the propeller bracket 15 so as to rotate the propeller an extent depending upon the amount of movement of the sleeve, which in turn depends upon the amount of rotation of the hand wheel 57. Through the reduction caused by. the difference in size of the gears 55 and 54 and the threaded connection between the gear hub 53 and bracket 52, such movement can be very accurately gauged and a very small change in the pitch of the propeller blades can be accurately obtained.

Although I have described one form of pitch controlling mechanism in detail, it will be apparent that various changes, additions, omissions and substitutions can be made thereinwithout departing from the spirit of this invention or the scope of the appended claims.

What I claim as new and desire to secure by Letters Patent is 1. The combination with a propeller blade of mechanism for shifting the blade so as to change the pitch thereof, means for posiing for retarding the movement of a portion of said merhanism with relation to said shaft and means connected with said mechanism for shiftin the blade about its axis when the rotation 0 part of said mechanism is retarded.

3. The combination with a propeller shaft having a blade associated therewith, of a blade shifting crank connected thereto, a shaft for operating said crank, a shaft operating gear rotatably mounted on said propeller shaft, means for locking said gear against movement with relation to said propeller shaft so as to cause the gear to normally rotate therewith, and an operatin mechanism for releasing said gear from sai locking means and for rotating the same with relation to said propeller shaft so as to operate said crank shaft and shift said blade about its axis.

4. The combination with a propeller shaft having a blade associated therewith, of a mechanism for shifting said blade about its axis, including an operating gear mounted on and normally rotating with said propeller shaft, means for retarding rotation of said gear relative to the rotation of said shaft and means for transmitting the relative rotation of said gear to said blade for shifting the same about its axis.

5. The combination with a propeller shaft having a blade associated therewith, of a blade shifting mechanism supported on said propeller shaft and rotatable therewith and including a gear connected to said blade, manually operable means for causing relative movement between said gear and said shaft for shifting said blade so as to reverse the pitch thereof and means for shifting said mechanism longitudinally of said propeller shaft for varying the pitch of said blade.

6. The combination with a propeller shaft having a propeller blade associated therewith, of a support for said blade secured to said shaft, mechanism mounted on said support and rotatable with said shaft a pitch reversing gear forming a portion of said mechanism means for retarding the rotation of said gear relative to the rotation of said mechanism for reversing the pitch of said blade and means for moving said reversing mechanism longitudinally of said shaft on iaidi support for varying the pitch of said la e.

7. The combination with a propeller shaft having a propeller blade associated therewith, of a crank shaft having a crank connected to said blade for shifting said blade' about its axis, a ear rotatably mounted on the propeller sha t for rotating said crank shaft and means for moving said gear longitudinally on said propeller shaft to change the pitch of said blade.

8. The combination with a propeller shaft having a propeller blade associated therewith, of a gear connected to said blade for shifting said blade about its axis, spring pressed pawls for locking said gear against movement with relation to said propeller shaft so as to hold said blade against rotation about its own axis, means for releasing said gear and causing relative rotation of said gear with relation to the rotation of said propeller shaft so as to reverse the pitch of said blade and means for shifting said gear bodily for varying the pitch of said blade.

9. n a pitch reversing and pitch adjusting mechanism for propeller blades, in combination, means for reversing the pitch of the blades, and means for changing the position of the reversing means to adjust the pitch of said blades.

10. In a pitch reversing and pitch adjusting mechanism for propellor blades, in combination, a propeller shaft having blades turnably mounted thereon, means on said shaft effective upon relative movement therebetween to reverse the pitch of said blades, and means disposed to move the reversing means along said shaft for varying the pitch of said blades.

11. The combination with a propeller shaft having a propeller blade associated therewith. of a stationary housing, a gear mounted on said shaft and normally rotating therewith. means associated with said stationary housing for retarding the movement of the said gear with relation to said shaft and means associated with said gear for shifting the blade about its axis when the rotation of said gear is retarded.

12. The combination with a propeller shaft having a. pro )eller blade associated therewith, of a stationary housing, a member slidably mounted on said shaft and rotatable therewith, a gear rotatably mounted on said shaft, means for locking said gear to said member so as to cause the same to rotate therewith means associated with said housing for releasing said gear and for retarding the rotation thereof relative to said shaft, and means connected to said blade for reversing the pitch of the blade.

13. The combination with a propeller shaft having a propeller blade thereon, of mechanism attached to said blade for reversing the pitch thereof, a gear rotatably mounted on said propeller shaft adapted to operate said mechanism, means for retarding the rotation of said gear relative to said shaft for operating said reversing mechanism, and means for shifting said gear longitudinally on said shaft for adjusting the pitch of said blade.

14. The combination with a propeller shaft having a propeller blade rotatable therewith, a member slidably mounted on and rotatable with said shaft, a gear rotatably mounted on said member, means for locking said gear to said member for causing the same to rotate therewith, a brake drum mounted on said member and yieldably connected to said gear, means on said drum for releasing said locking means for retarding the rotation of said gear in relation to said member, and means operable by said gear for reversing the pitch of said blade when the gear is being rotated relative to the shaft.

15. The combination with a propeller shaft having a propeller blade associated therewith, of a crank shaft, a crank connecting said crank shaft to said blade, a gear mounted on said propeller shaft for operating said crank shaft and means for rotating said gear relative to said propeller shaft so as to reverse the pitch of said blade, said means including a brake drum normally rotating with said gear, and means on said brake drum adapted to stop the rotation of said gear when the rotation of said drum is retarded.

16. The combination with a propeller shaft having a propeller blade secured thereto, of a blade shifting crank connected thereto, a shaft for operating said crank, a sleeve slidably mounted on and rotatable with said propeller shaft, a crank shaft operating gear rotatably mounted on said-sleeve, means for locking said gear to said sleeve so as to prevent movement of said crank shaft, means for releasing said gear and for retarding rotation thereof in relation to said propeller shaft so as to operate said crank shaft and reverse the pitch of said blade, and means for positioning said sleeve on said propeller shaft to adjust the pitch of said blade.

17. The combination with a propeller shaft having a propeller blade mounted thereon, of a blade shifting crank connected thereto, a shaft for operating said crank, a sleeve slidably mounted on and rotatable with said propeller shaft, a crank shaft operating gear rotatably mounted on said sleeve, spring pressed pawls for locking said gear to said sleeve so as to prevent movement of said crank shaft, a brake drum rotatably mounted on said sleeve and yieldably connected to said gear, means for retarding the rotation of said drum and means on said drum for releasing said locking means, projections on said a blade shifting crank connected thereto, a shaft for operating said crank, a sleeve slidably mounted on and rotatable with said propeller shaft, a crank shaft operating gear ro- 5 tatably mounted on said sleeve, means for locking said gear to said sleeve and means for releasing said gear and for rotating the same relative to said shaft so as to operate said crank shaft for turning said blade about 10 the axis thereof, said means including a brake drum mounted on said sleeve having beveled lugs adapted to engage said locking means when the rotation of the drum is retarded for releasing said gear, and lugs on said drum 15 adapted to engage lugs on said gear for rotating the same.

In testimony whereof, I have hereunto subscribed my name this 12th day of March, 1929.

SIDNEY T. CARTER.

CERTIFICATE OF CORRECTION.

Patent No. 1,876,608. September 13, 1932.

SIDNEY T. CARTER.

it is hereby certified that error appears in,the printed specification of the above numbered patent requiring correction as follows: Page 1, line 34, for "hen" read "been"; and line80, for "casting" read "hub"; page 3, line 76, claim 2, for the misspelled word "mcrhanism" read "mechanism"; page 4, line 29, claim 10, for "propeller" read "propeller"; and that the said Letters Patent should be read with these corrections therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 29th day of November, A. D. 1932.

r M. J. Moore.

(Seal) Acting Commissioner of Patents.

a blade shifting crank connected thereto, a shaft for operating said crank, a sleeve slidably mounted on and rotatable with said propeller shaft, a crank shaft operating gear ro- 5 tatably mounted on said sleeve, means for locking said gear to said sleeve and means for releasing said gear and for rotating the same relative to said shaft so as to operate said crank shaft for turning said blade about 10 the axis thereof, said means including a brake drum mounted on said sleeve having beveled lugs adapted to engage said locking means when the rotation of the drum is retarded for releasing said gear, and lugs on said drum 15 adapted to engage lugs on said gear for rotating the same.

In testimony whereof, I have hereunto subscribed my name this 12th day of March, 1929.

SIDNEY T. CARTER.

CERTIFICATE OF CORRECTION.

Patent No. 1,876,608. September 13, 1932.

SIDNEY T. CARTER.

it is hereby certified that error appears in,the printed specification of the above numbered patent requiring correction as follows: Page 1, line 34, for "hen" read "been"; and line80, for "casting" read "hub"; page 3, line 76, claim 2, for the misspelled word "mcrhanism" read "mechanism"; page 4, line 29, claim 10, for "propeller" read "propeller"; and that the said Letters Patent should be read with these corrections therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 29th day of November, A. D. 1932.

r M. J. Moore.

(Seal) Acting Commissioner of Patents. 

